Physics
Wien's Displacement Law
Quick fact
The surface of the Sun (about 5,500°C) peaks in the yellow-green part of the spectrum, which is why we see it as white in space. Cooler red stars peak in the infrared, while hotter blue stars peak in the ultraviolet.
Why this is interesting
Why does a piece of metal glow red when hot, then white, then blue as it heats up? The answer lies in a simple but powerful rule: as temperature rises, the peak color of emitted light shifts to shorter wavelengths.